Copper complex compounds with ethylenediamine

Copper complexes (152) of o-hydroxy-o -(p-aminoethylamino)diarylazo compounds have been prepared ° by the reaction of the corresponding o-chloro-o -hydroxydiarylazo compounds and ethylenediamine in the presence of copper(II) ions (c/. Section 58.2.3. l(iii)(c)). Dyestuffs of this type have been evaluated on nylon but are reported to have very poor fastness properties. Copper complexes such as (153) have been preparedby similar methods. Other, related tetradentate diarylazo compounds, e.g. (154), (155) and (156), are obtained by the reaction of a suitable diazonium salt with the appropriate diarylamine. Chromium(III) and cobalt(III) complexes of dyes of this type, in which the coordination sphere of the metal is completed by a colourless bidentate ligand such as ethylenediamine, salicylic acid or 8-hydroxyquinoline, are reported to have dyeing properties on wool similar to those of the comparably charged 2 1 complexes derived from tri-... 

Curtis and coworkers first reported the amine-imine linkage formation of the type shown in Figure 1 by condensation of two molecules of acetone with ethylenediamines in the presence of nickel(II) or copper(II) ions ( 1, 2 3). It was also shown that this type of reaction generally occurs with several carbonyl compounds (4, 5). Later, the mechanism of the linkage formation and the stereoisomerism and some reactions of the metal complexes with macrocycles were investigated in detail (5, 6, 7 ). 

Kx for copper (II)-diamine complex is 10.36 and 9.45 for 1,2-ethanediamine and 1,3-propanediamine, respectively (-2)]. The large difference in the stabilities of the two copper (II)-diamine complexes is attributed to an unfavorable entropy effect associated with an increase in the size of the metal-chelate ring (2). Extrapolating to the / -ketoimine derivatives, it seems reasonable to expect that the stability of bisacetylacetonetrimethylenediiminocopper(II) would be less than that of the ethylenediamine analog and to suspect that the former compound is less stable than bis-(4-iminopentane-2-ono) copper (II). That this is reasonable is... 

One of the earliest references to a reaction in solution, which, as we now realize, depends upon the formation of a coordination compound, was recorded by Pliny who stated that the adulteration of copper sulfate by iron sulfate could be detected by testing with a strip of papyrus soaked in gall-nuts, when a black colour developed if iron were present. A. Libavius (1540-1616) noted how ammmonia present in water could be detected by the blue colour formed with a copper salt and A. Jacquelain (1846) actually determined copper salts in terms of the blue colour formed on adding ammonia. Later developments used coordination compounds formed from ethylenediamine and other polyamines.3 T. J. Herapath determined iron(III) as its red isothiocyanate complex in 1852 and the basic procedure is used today.3... 

The very different basicities of water and of ammonia lead to different reactivity patterns for iSNlcb base hydrolyses of cobalt(iii) compounds. The latest contribution in this area has been a study of base hydrolysis of a series of complexes [Co(NH3)6(RNHa)] + in liquid ethylenediamine. The basicity or solvating power of the solvent determines the form of the rate law for substitutions at copper(ii)-Schiff base complexes. The term corresponding to solvolysis is, of course, only significant for solvents with an affinity for copper(ii). ... 

Careful optimization of the process leads to efimination of the minor explosions and improved yield. The method itself has however been superseded by the diamine complex route. These complexes are synthesized by the reaction of acidic copper salt of 5-nitrotetrazole with the relevant diamine (mostly 1,2-ethylenediamine or less frequently 1,3-diaminopropane) in the presence of copper sulfate [4,40,41,46, 56,66]. These coordination compounds could be readily purified by recrystallization from water and they are safer and easier to handle in the dry state than the sodium salt (1,2-ethylenediamine complex only bums when impacted by 2.5 kg hammer from 50 cm) [42, 46]. 

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